The making of a flower: control of floral meristem identity in Arabidopsis

During the reproductive phase of a plant, shoot meristems follow one of two developmental programs to produce either flowers or vegetative shoots. The decision as to which meristems give rise to flowers, and when they do so, determines the general morphology of an inflorescence. Molecular and geneti c research in Arabidopsis and other model species has identified several ge nes that control the identity that a meristem will adopt, These meristem id entity genes are activated in response to developmental and environmental c ues, and can be assigned to three basic categories: those required either t o initiate or maintain the floral program in some meristems and those requi red to maintain the vegetative program in others.